The oceans are dying but they can be saved.

The world’s oceans are one of the central pillars responsible for balancing much of the global climate, apart from being the habitat for uncountable species of marine life. However, the deep blue seas have been put under enormous stress as a result of human activity such as overfishing and pollution. Now, a new review published in Nature provides hope – and an action plan – that our oceans can be restored within 30 years.

According to the researchers, the oceans have sustained worrisome damage owing to human activity, in particular plastic pollution, climate change, and increasing acidification. This has continued without interruption, despite the fact that conserving the oceans and using them sustainably is one of the United Nations’ Sustainable Development Goals.

But the authors of the study also highlight the impressive and often surprising resilience of marine ecosystems: “Regional examples of impressive resilience include the rebound of fish stocks during World War I and World War II following a marked reduction in fishing pressure, the recovery since 1958 of coral reefs in the Marshall Islands from megatons of nuclear tests and the improved health of the Black Sea and the Adriatic Sea following a sudden reduction in the application of fertilizers after the collapse of the Soviet Union.”

Even though these stories of recovery are not the result of environmental protection measures, they nevertheless show how effective ecosystems are restoring themselves when given the time and space to do so. The results could be even better if ecosystems were to receive active support in the form of conservation action.

“Our study documents the recovery of marine populations, habitats and ecosystems following past conservation interventions,” said Carlos Duarte, the review’s lead author. “It provides specific, evidence-based recommendations to scale proven solutions globally.”

To that end, the authors point to the importance of coral and oyster reefs, salt marshes, mangroves and seagrass, kelp, fisheries, and megafauna in aiding ocean recovery, and recommend protective measures. The cost of sustained policy implementation in that regard is estimated to amount to $10-20 billion per year until 2050. A gigantic sum, but one that the researchers predict will be met with considerable returns: “The economic return from this commitment will be considerable, around $10 per $1 invested and in excess of one million new jobs” – not counting the positive returns of ecotourism to protected areas.

However, to reap these benefits, the international community needs to act quickly, and although several projects to mitigate environmental damage and pollution are being devised, the window of opportunity to turn the ship around is narrowing. “We are at a point at which we can choose between a legacy of a resilient and vibrant ocean or an irreversibly disrupted ocean, for the generations to follow.”